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Finding the Fourth Proportional to 378.25, 521.89 and 289.83

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Solution

The fourth proportional to 378.25, 521.89 and 289.83 is: 399.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.25 : 521.89 = 289.83 : x
  2. Step 2: Convert to fraction form
    378.25/521.89 = 289.83/x
  3. Step 3: Cross multiply
    378.25x = 521.89 × 289.83
  4. Step 4: Simplify right side
    378.25x = 151,261.70
  5. Step 5: Solve for x
    x = 151,261.70/378.25
  6. Step 6: Final answer
    x = 399.90

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.